Arterial Thrombosis and Acute Limb Ischemia as a Complication of COVID-19 Infection.

COVID-19 refers to viral respiratory infections and is the predisposing factor for the development of venous and arterial thrombotic events due to a pronounced inflammatory response, platelet activation, endothelial dysfunction, and stasis. Recent studies have confirmed a high incidence of thromboembolic events, especially in the group of patients with severe coronavirus pneumonia. There have been an increasing number of reports of peripheral arterial thrombosis as well. Most cases of arterial thrombosis are noted in critical ill patients in intensive care setting. However, an increase of adverse arterial events was also noted in cases of asymptomatic or mild forms of COVID-19. Herein, we report a case of patient with asymptomatic SARS-CoV-2 infection, who developed a threatening lower limb ischemia. Our own clinical observation suggests that COVID-19-associated arterial thrombosis can be successfully treated by embolectomy, administration of in-hospital parenteral anticoagulation, and continuation of antithrombotic therapy with a "vascular" dose of rivaroxaban after discharge.

Hematological changes as a consequence of COVID-19 and its vaccines / Alteraciones hematológicas como consecuencia de COVID-19 y sus vacunas

El virus SARS-CoV-2 continúa infectando a millones de individuos en el mundo. Aunque los síntomas más frecuentes observados en los pacientes con COVID-19 son fiebre, fatiga y tos, en los casos severos la hipercoagulabilidad y la inflamación son dos condiciones que pueden producir complicaciones y causar daño en órganos, poniendo en riesgo la vida del paciente. Con el fin de clasificar a los pacientes durante el triaje, se han explorado diferentes marcadores hematológicos, incluidos el recuento de plaquetas, linfocitos y eosinófilos, y la relación neutrófilos/ linfocitos, entre otros. Por su parte, para la evaluación de las coagulopatías, se vienen determinando marcadores como el dímero D y el fibrinógeno. En esta revisión se abordan las coagulopatías y los parámetros hematológicos en pacientes con COVID-19, al igual que las anormalidades en la coagulación como la trombocitopenia trombótica inmune inducida por las vacunas contra el SARS-CoV-2

The SARS-CoV-2 virus continues to infect millions of individuals around the world. Although the most frequent symptoms observed in patients with COVID-19 are fever, fatigue and cough, in severe cases hypercoagulability and inflammation are two conditions that can cause complications and organ failure, putting the patient's life at risk. In order to classify patients during triage, different hematological markers have been explored, including platelet, lymphocyte, and eosinophil counts, and the neutrophil/lymphocyte ratio, among others. Furthermore, for the evaluation of coagulopathies, markers such as D-dimer and fibrinogen are being evaluated. This review addresses the coagulopathies and hematological parameters in patients with COVID-19, as well as coagulation abnormalities such as immune thrombotic thrombocytopenia induced by SARS-CoV-2 vaccines

Cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia in middle-income countries.

BACKGROUND: Adenovirus-based COVID-19 vaccines are extensively used in low- and middle-income countries (LMICs). Remarkably, cases of cerebral venous sinus thrombosis due to vaccine-induced immune thrombotic thrombocytopenia (CVST-VITT) have rarely been reported from LMICs. AIMS: We studied the frequency, manifestations, treatment, and outcomes of CVST-VITT in LMICs. METHODS: We report data from an international registry on CVST after COVID-19 vaccination. VITT was classified according to the Pavord criteria. We compared CVST-VITT cases from LMICs to cases from high-income countries (HICs). RESULTS: Until August 2022, 228 CVST cases were reported, of which 63 were from LMICs (all middle-income countries [MICs]: Brazil, China, India, Iran, Mexico, Pakistan, Turkey). Of these 63, 32 (51%) met the VITT criteria, compared to 103 of 165 (62%) from HICs. Only 5 of the 32 (16%) CVST-VITT cases from MICs had definite VITT, mostly because anti-platelet factor 4 antibodies were often not tested. The median age was 26 (interquartile range [IQR] 20-37) versus 47 (IQR 32-58) years, and the proportion of women was 25 of 32 (78%) versus 77 of 103 (75%) in MICs versus HICs, respectively. Patients from MICs were diagnosed later than patients from HICs (1/32 [3%] vs. 65/103 [63%] diagnosed before May 2021). Clinical manifestations, including intracranial hemorrhage, were largely similar as was intravenous immunoglobulin use. In-hospital mortality was lower in MICs (7/31 [23%, 95% confidence interval (CI) 11-40]) than in HICs (44/102 [43%, 95% CI 34-53], p = 0.039). CONCLUSIONS: The number of CVST-VITT cases reported from LMICs was small despite the widespread use of adenoviral vaccines. Clinical manifestations and treatment of CVST-VITT cases were largely similar in MICs and HICs, while mortality was lower in patients from MICs.

Bilateral pulmonary embolism associated with peripheral blood eosinophilia and positive antiphospholipid antibodies in a patient with cellulitis.

Key Clinical Message: This report described the pathophysiology, diagnostic workup, and management of thrombosis possibly associated with peripheral blood eosinophilia and transient positive antiphospholipid antibodies in the setting of cellulitis. Abstract: Peripheral blood eosinophilia is a risk factor for thrombosis and the presence of other prothrombotic factors such as antiphospholipid antibodies can potentiate that risk. The authors present a case of acute pulmonary embolism which developed at the peak of eosinophilia, later found to have transient positive antiphospholipid antibodies in a male patient with right lower limb cellulitis and a history of intravenous drug abuse. This report illustrates the pathophysiology, diagnosis workup, and therapeutic options of thrombosis possibly associated with peripheral blood eosinophilia and positive antiphospholipid antibodies, which include anticoagulants, corticosteroids, and immunosuppressants. Clinicians should be aware of this possible association which may guide the choice and duration of anticoagulants. Although direct oral anticoagulants are effective anticoagulants in various thromboembolic events, studies showed unfavorable outcomes for their use in antiphospholipid syndrome.

Diagnostic and Therapeutic Challenges of Concurrent Intracranial Hemorrhage and Cerebral Venous Thrombosis in a Patient With Acute Lymphoblastic Leukemia: A Case Report and Literature Review.

Cerebral venous sinus thrombosis (CVST) is a cerebrovascular condition due to the thrombosis of cerebral venous sinuses, leading to intracranial hemorrhage, increased intracranial pressure, focal deficit, seizure, toxic edema, encephalopathy, and death. The diagnosis and therapeutic approach of CVST remain challenging because of its highly nonspecific clinical presentation including headaches, seizures, focal neurologic deficits, and altered mental status, etc. Anticoagulation is the mainstay of CVST treatment and should be started as soon as the diagnosis is confirmed. Here, we present the case of a 34-year-old male construction worker who presented to the emergency department with a complaint of right chest wall pain and swelling. He was admitted to the hospital following a diagnosis of anterior chest wall abscess and mediastinitis. During hospitalization, his complete blood count revealed pancytopenia with blast cells, and bone marrow biopsy revealed 78.5% lymphoid blasts by aspirate differential count and hypercellular marrow (100%) with decreased hematopoiesis. He developed concurrent CVST and intracranial hemorrhage while receiving CALGB10403 (vincristine, daunorubicin, pegaspargase, prednisone) with intrathecal cytarabine induction chemotherapy for acute lymphoblastic leukemia (ALL). The patient failed two standard chemotherapy for ALL and achieved remission while on third-line chemotherapy with an anti-CD19 monoclonal antibody, blinatumomab. Although this patient had an MRI scan of the brain with multiple follow-up non-contrast CT scans, it was CT angiography that revealed CVST. This showed the diagnostic challenge in CVST, with CT and MRI venography having excellent sensitivity in diagnosing CVST. Risk factors for CVST in our patient were ALL and its intensive induction chemotherapy with pegaspargase.

A review of venous thromboembolism in India.

Venous thromboembolism (VTE), which entails the formation of a thrombus (blood clot) in a vein, has a significant disease burden worldwide. While VTE has traditionally been considered to predominantly affect Caucasian populations, recent studies have indicated a gradual shift in the disease burden towards Asian populations, with added significance of it being a key driver of post-operative mortality. It is imperative to develop a sound understanding of the various factors that affect VTE in stratified local populations. However, there is a glaring paucity of quality data on VTE and its ramifications among Indians - both in terms of quality of life and cost of healthcare. This review aims to throw light on the disease burden, epidemiology, risk factors, environmental factors, food and nutrition that plays a key role in VTE. We also explored the association of VTE with coronavirus disease 2019 to grasp the interplay between the two most significant public health crises of our time. It is vital to place a special emphasis on future research on VTE in India to plug the gaps, which exist in our current knowledge of the disease, particularly with respect to Indian population.

Validation of the CoVID-TE model as a tool to predict thrombosis, bleeding, and mortality in the oncology patient with Sars-Cov-2 infection: a study by the SEOM cancer and thrombosis group.

PURPOSE: The CoVID-TE model was developed with the aim of predicting venous thrombotic events (VTE) in cancer patients with Sars-Cov-2 infection. Moreover, it was capable of predicting hemorrhage and mortality 30 days following infection diagnosis. The model is pending validation. METHODS/PATIENTS: Multicenter retrospective study (10 centers). Adult patients with active oncologic disease/ antineoplastic therapy with Sars-Cov-2 infection hospitalized between March 1, 2020 and March 1. 2022 were recruited. The primary endpoint was to study the association between the risk categories of the CoVID-TE model and the occurrence of thrombosis using the Chi-Square test. Secondary endpoints were to demonstrate the association between these categories and the occurrence of post-diagnostic Sars-Cov-2 bleeding/ death events. The Kaplan-Meier method was also used to compare mortality by stratification. RESULTS: 263 patients were enrolled. 59.3% were men with a median age of 67 years. 73.8% had stage IV disease and lung cancer was the most prevalent tumor (24%). A total of 86.7% had an ECOG 0-2 and 77.9% were receiving active antineoplastic therapy. After a median follow-up of 6.83 months, the incidence of VTE, bleeding, and death 90 days after Sars-Cov-2 diagnosis in the low-risk group was 3.9% (95% CI 1.9-7.9), 4.5% (95% CI 2.3-8.6), and 52.5% (95% CI 45.2-59.7), respectively. For the high-risk group it was 6% (95% CI 2.6-13.2), 9.6% (95% CI 5.0-17.9), and 58.0% (95% CI 45.3-66.1). The Chi-square test for trends detected no statistically significant association between these variables (p > 0.05). Median survival in the low-risk group was 10.15 months (95% CI 3.84-16.46), while in the high-risk group it was 3.68 months (95% CI 0.0-7.79). The differences detected were not statistically significant (p = 0.375). CONCLUSIONS: The data from our series does not validate of the CoVID-TE as a model to predict thrombosis, hemorrhage, or mortality in cancer patients with Sars-Cov-2 infection.

NLRP3 inflammasome and interleukin-1 contributions to COVID-19-associated coagulopathy and immunothrombosis.

Immunothrombosis - immune-mediated activation of coagulation - is protective against pathogens, but excessive immunothrombosis can result in pathological thrombosis and multiorgan damage, as in severe Coronavirus Disease 2019 (COVID-19). The NACHT-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome produces major proinflammatory cytokines of the interleukin (IL)-1 family, IL-1ß and IL-18, and induces pyroptotic cell death. Activation of the NLRP3 inflammasome pathway also promotes immunothrombotic programs including release of neutrophil extracellular traps and tissue factor by leukocytes, and prothrombotic responses by platelets and the vascular endothelium. NLRP3 inflammasome activation occurs in patients with COVID-19 pneumonia. In preclinical models, NLRP3 inflammasome pathway blockade restrains COVID-19-like hyperinflammation and pathology. Anakinra, recombinant human IL-1 receptor antagonist, showed safety and efficacy, and is approved for the treatment of hypoxemic COVID-19 patients with early signs of hyperinflammation. The non-selective NLRP3 inhibitor colchicine reduced hospitalization and death in a subgroup of COVID-19 outpatients, but is not approved for the treatment of COVID-19. Additional COVID-19 trials testing NLRP3 inflammasome pathway blockers are inconclusive or ongoing. We herein outline the contribution of immunothrombosis to COVID-19-associated coagulopathy, and review preclinical and clinical evidence suggesting an engagement of the NLRP3 inflammasome pathway in the immunothrombotic pathogenesis of COVID-19. We also summarize current efforts to target the NLRP3 inflammasome pathway in COVID-19, and discuss challenges, unmet gaps and the therapeutic potential that inflammasome-targeted strategies may provide for inflammation-driven thrombotic disorders including COVID-19.

Investigating the risk of deep vein thrombosis with JAK inhibitors: a disproportionality analysis using FDA Adverse Event Reporting System Database (FAERS).

BACKGROUND: Janus kinase (JAK) inhibitors are immune-modulating medications used to treat conditions including rheumatoid arthritis, COVID-19, ulcerative colitis, atopic dermatitis, myelofibrosis, and polycythemia Vera. However, these medications have been associated with higher incidence of deep vein thrombosis. The objective of this study was to investigate potential safety signals for DVT associated with JAK inhibitors using disproportionality analysis from the FDA Adverse Event Reporting System (FAERS) database. RESEARCH DESIGN AND METHODS: The authors retrospectively investigated case/non-case analysis using Openvigil 2.1-MedDRA-v24 (2004Q1 to 2022Q4). The preferred term used was 'deep vein thrombosis,' and the drugs included were baricitinib, tofacitinib, and upadacitinib. Reporting odds ratio, proportional reporting ratio, and information component were used to detect signals. RESULTS: Overall 114,005 AE reports related to JAK inhibitors were identified, of which 647 reports (baricitinib - 169, tofacitinib - 425, and upadacitinib - 53) associated with DVT were obtained from FAERS. On analysis, baricitinib and tofacitinib had greater signal strength for age group of 65-100 years and all three had the highest signal strength for male gender. CONCLUSIONS: Our study identified signals for DVT with baricitinib, tofacitinib, and upadacitinib. Further research using well-designed epidemiological data is needed to validate these results.

Potential Benefits of Omega-3 Polyunsaturated Fatty Acids (N3PUFAs) on Cardiovascular Health Associated with COVID-19: An Update for 2023.

The accumulating literature demonstrates that omega-3 polyunsaturated fatty acid (n-3 polyunsaturated fatty acid, N3PUFA) can be incorporated into the phospholipid bilayer of cell membranes in the human body to positively affect the cardiovascular system, including improving epithelial function, decreasing coagulopathy, and attenuating uncontrolled inflammatory responses and oxidative stress. Moreover, it has been proven that the N3PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are precursors of some potent endogenous bioactive lipid mediators that mediate some favorable effects attributed to their parent substances. A dose-response relationship between increased EPA and DHA intake and reduced thrombotic outcomes has been reported. The excellent safety profile of dietary N3PUFAs makes them a prospective adjuvant treatment for people exposed to a higher risk of cardiovascular problems associated with COVID-19. This review presented the potential mechanisms that might contribute to the beneficial effects of N3PUFA and the optimal form and dose applied.

Recombinant human DNase-I improves acute respiratory distress syndrome via neutrophil extracellular trap degradation.

BACKGROUND: Respiratory failure is the primary cause of death in patients with COVID-19, whereas coagulopathy is associated with excessive inflammation and multiorgan failure. Neutrophil extracellular traps (NETs) may exacerbate inflammation and provide a scaffold for thrombus formation. OBJECTIVES: The goal of this study was to determine whether degradation of NETs by recombinant human DNase-I (rhDNase), a safe, Food and Drug Administration-approved drug, reduces excessive inflammation, reverses aberrant coagulation, and improves pulmonary perfusion after experimental acute respiratory distress syndrome (ARDS). METHODS: Intranasal poly(I:C), a synthetic double-stranded RNA, was administered to adult mice for 3 consecutive days to simulate a viral infection, and these subjects were randomized to treatment arms, which received either an intravenous placebo or rhDNase. The effects of rhDNase on immune activation, platelet aggregation, and coagulation were assessed in mice and donor human blood. RESULTS: NETs were observed in bronchoalveolar lavage fluid and within regions of hypoxic lung tissue after experimental ARDS. The administration of rhDNase mitigated peribronchiolar, perivascular, and interstitial inflammation induced by poly(I:C). In parallel, rhDNase degraded NETs, attenuated platelet-NET aggregates, reduced platelet activation, and normalized the clotting time to improve regional perfusion, as observed using gross morphology, histology, and microcomputed tomographic imaging in mice. Similarly, rhDNase reduced NETs and attenuated platelet activation in human blood. CONCLUSION: NETs exacerbate inflammation and promote aberrant coagulation by providing a scaffold for aggregated platelets after experimental ARDS. Intravenous administration of rhDNase degrades NETs and attenuates coagulopathy in ARDS, providing a promising translational approach to improve pulmonary structure and function after ARDS.

Strategies for the Management of Spike Protein-Related Pathology.

In the wake of the COVID-19 crisis, a need has arisen to prevent and treat two related conditions, COVID-19 vaccine injury and long COVID-19, both of which can trace at least part of their aetiology to the spike protein, which can cause harm through several mechanisms. One significant mechanism of harm is vascular, and it is mediated by the spike protein, a common element of the COVID-19 illness, and it is related to receiving a COVID-19 vaccine. Given the significant number of people experiencing these two related conditions, it is imperative to develop treatment protocols, as well as to consider the diversity of people experiencing long COVID-19 and vaccine injury. This review summarizes the known treatment options for long COVID-19 and vaccine injury, their mechanisms, and their evidentiary basis.

Common Coagulopathies Associated With COVID-19 Patients.

The coronavirus disease 2019 (COVID-19) outbreak, which first appeared in the Chinese province of Hubei city of Wuhan, has been spreading internationally since December 2019. The World Health Organization (WHO) declared the coronavirus illness from 2019 to be a pandemic on March 11, 2020. Patients hospitalised with severe coronavirus or comorbid conditions (like cardiovascular disease and obesity) are linked to a worse prognosis. The rise in D-dimer and its relationship to prognosis are the most often documented aberrations in coagulation/fibrinolysis in COVID-19. However, the D-dimer assessment's utility is not limitless. Since the coagulation/fibrinolytic state might occasionally change over a short period of time, routine exams are also advantageous in understanding the relevance of the inquiry. Both thrombotic and hemorrhagic diseases should be taken into consideration, despite the fact that the pathophysiology of disseminated intravascular coagulation (DIC) linked with coronavirus disease 19 differs significantly from that of septic disseminated intravascular coagulation. Coagulation as well as fibrinolysis indicators are used to make the diagnosis of COVID-19 thrombosis, which encompasses both macro- and micro-thrombosis. Compared to bacterial-sepsis-associated coagulopathy/DIC, COVID-19 has a lower prevalence of prolonged prothrombin time, activated partial thromboplastin time, and decreased antithrombin activity. However, the causes of coagulopathy remain poorly understood. Hypoxia, endothelial injury, dysregulated immunological responses mediated by inflammatory cytokines, and lymphocyte cell death are thought to be implicated. While blood loss tends to be rare, it is uncertain if COVID-19 suffers from thrombosis or whether the current recommendations for regular venous thromboembolic dose are appropriate. It is important to decide on the COVID-19 therapy phases. Antiviral therapy, cytokine storm therapy, and thrombosis therapy are the steps. Future advancements are predicted, such as a therapy that combines heparin and nafamostat.

SARS-CoV-2 vaccination induced cerebral venous sinus thrombosis: Do megakaryocytes, platelets and lipid mediators make up the orchestra?

The COVID-19 vaccines comprised of adenoviral vectors encoding the Spike (S) glycoprotein of SARS-CoV-2 are highly effective but associated with rare thrombotic complications. The adenovirus vector infects epithelial cells expressing the coxsackievirus and adenovirus receptor (CAR). The S glycoprotein expressed locally stimulates neutralizing antibody and cellular immune responses. These vaccines have been associated with thromboembolic events including cerebral venous sinus thrombosis (CVST). S glycoprotein stimulates the expression of cyclooxygenase-2 (COX-2) and leads to massive generation of thromboxane A2 in COVID-19. Megakaryocytes express CAR and we postulate that S glycoprotein stimulated generation of thromboxane A2 leads to megakaryocyte activation, biogenesis of activated platelets and thereby increased thrombogenicity. Cerebral vein sinuses express podoplanin, a natural ligand for CLEC2 receptors on platelets. Platelets traversing through the cerebral vein sinuses could be further activated by thromboxane A2-dependent podoplanin-CLEC2 signaling, leading to CVST. A prothrombotic hormonal milieu, and increased generation of thromboxane A2 and platelet activation in healthy females compared to males is consistent with increased risk for CVST observed in women. We propose that antiplatelet agents targeting thromboxane A2 receptor signaling such as low-dose aspirin merit consideration for chemoprophylaxis when administering the adenovirus based COVID-19 vaccines to young adults at risk of thrombosis provided there are no contraindications.

Thromboembolic events in patients with paroxysmal nocturnal hemoglobinuria (PNH): Real world data of a Greek nationwide multicenter retrospective study.

Thrombosis is the most common and a life-threatening complication in patients with Paroxysmal Nocturnal Hemoglobinuria. One-third of patients with PNH experience at least one thromboembolic event during the course of the disease, with thrombosis being the most common cause of death in these patients. The mechanism of thrombosis in PNH is complex and continues to be of great research interest. Since the introduction of C5 complement inhibitors in the treatment of PNH, the incidence of thromboembolic events has decreased substantially. We retrospectively analyzed data concerning the thrombotic episodes of 41 patients with PNH from 14 different national hematology centers in Greece. Sixteen patients (39%) experienced at least one episode of thrombosis, including, seven (43.8%) at diagnosis, seven (43.8%) during the course of the disease and two (12.5%) patients prior to PNH diagnosis. Nearly half of these individuals (n=7, 43.8%) had multiple episodes of thrombosis during the course of their disease. The most common sites of thrombosis were intra-abdominal veins. Three out of 26 patients developed thrombosis while on eculizumab. In none of the 16 patients, the thrombotic event was fatal. Our findings, despite the small number of patients, confirmed that thrombosis continues to be a significant complication of PNH affecting more than one third of the patients.

Lipoprotein(a) Does Not Predict Thrombotic Events and In-Hospital Outcomes in Patients with COVID-19.

The prothrombotic and proinflammatory properties of lipoprotein(a) (Lp(a)) have been hypothesized to play a role in the pathogenesis of severe COVID-19; however, the prognostic impact of Lp(a) on the clinical course of COVID-19 remains controversial. This study aimed to investigate whether Lp(a) may be associated with biomarkers of thrombo-inflammation and the occurrence of thrombotic events or adverse clinical outcomes in patients hospitalized for COVID-19. We consecutively enrolled a cohort of patients hospitalized for COVID-19 and collected blood samples for Lp(a) assessment at hospital admission. A prothrombotic state was evaluated through D-dimer levels, whereas a proinflammatory state was evaluated through C-reactive protein (CRP), procalcitonin, and white blood cell (WBC) levels. Thrombotic events were marked by the diagnosis of deep or superficial vein thrombosis (DVT or SVT), pulmonary embolism (PE), stroke, transient ischemic attack (TIA), acute coronary syndrome (ACS), and critical limb ischemia (CLI). The composite clinical end point of intensive care unit (ICU) admission/in-hospital death was used to evaluate adverse clinical outcomes. Among 564 patients (290 (51%) men, mean age of 74 ± 17 years) the median Lp(a) value at hospital admission was 13 (10-27) mg/dL. During hospitalization, 64 (11%) patients were diagnosed with at least one thrombotic event and 83 (15%) patients met the composite clinical end point. Lp(a), as either a continuous or categorical variable, was not associated with D-dimer, CRP, procalcitonin, and WBC levels (p > 0.05 for all correlation analyses). In addition, Lp(a) was not associated with a risk of thrombotic events (p > 0.05 for multi-adjusted odds ratios) nor with a risk of adverse clinical outcomes (p > 0.05 for multi-adjusted hazard ratios). In conclusion, Lp(a) does not influence biomarkers of plasma thrombotic activity and systemic inflammation nor has any impact on thrombotic events and adverse clinical outcomes in patients hospitalized for COVID-19.

Fondaparinux Sodium: Recent Advances in the Management of Thrombosis.

Fondaparinux sodium is a chemically synthesized selective factor Xa inhibitor approved for the prevention and treatment of venous thromboembolic events, that is, deep vein thrombosis, pulmonary embolism, and superficial vein thrombosis, in acutely ill (including those affected by COVID-19 or cancer patients) and those undergoing surgeries. Since its approval in 2002, the efficacy and safety of fondaparinux is well demonstrated by many clinical studies, establishing the value of fondaparinux in clinical practice. Some of the advantages with fondaparinux are its chemical nature of synthesis, minimal risk of contamination, 100% absolute bioavailability subcutaneously, instant onset of action, a long half-life, direct renal excretion, fewer adverse reactions when compared with direct oral anticoagulants, and being an ideal alternative in conditions where oral anticoagulants are not approved for use or in patients intolerant to low molecular weight heparins (LMWH). In the last decade, the real-world use of fondaparinux has been explored in other conditions such as acute coronary syndromes, bariatric surgery, in patients developing vaccine-induced immune thrombotic thrombocytopenia (VITT) and in pregnant women with heparin-induced thrombocytopenia (HIT), or those intolerant to LMWH. The emerging data from these studies have culminated in recent updates in the guidelines that recommend the use of fondaparinux under various conditions. This paper aims to review the recent data and the subsequent updates in the recommendations of various guidelines on the use of fondaparinux sodium.

ANTIPHOSPHOLIPID ANTIBODIES AND VASCULAR THROMBOSIS IN PATIENTS WITH THE MOST SEVERE FORMS OF COVID-19

BackgroundThe presence of antiphospholipid antibodies (aPL) has been observed in patients with COVID-19 (1,2), suggesting that they may be associated with deep vein thrombosis, pulmonary embolism, or stroke in severe cases (3). Antiphospholipid syndrome (APS) is a systemic autoimmune disorder and the most common form of acquired thrombophilia globally. At least one clinical criterion, vascular thrombosis (arterial, venous or microthrombosis) or pregnancy morbidity and at least one laboratory criterion- positive aPL two times at least 12 weeks apart: lupus anticoagulant (LA), anticardiolipin (aCL), anti-β2-glycoprotein 1 (anti-β2GPI) antibody, have to be met for international APS classification criteria(4). Several reports also associate anti-phosphatidylserine/prothrombin antibodies (aPS/PT) with APS.ObjectivesTo combine clinical data on arterial/venous thrombosis and pregnancy complications before and during hospitalisation with aPL laboratory findings at 4 time points (hospital admission, worsening of COVID-19, hospital discharge, and follow-up) in patients with the most severe forms of COVID-19 infection.MethodsPatients with COVID-19 pneumonia were consequetively enrolled, as they were admitted to the General hospital Pancevo. Exclusion criteria were previous diagnosis of inflammatory rheumatic disease and diagnosis of APS. Clinical data were obtained from the medical records. Laboratory results, including LA, aCL, anti-β2GPI, and aPS/PT antibodies were taken at hospital admission, worsening (defined as cytokine storm, connection of the patient to the respirator, use of the anti-IL-6 drug- Tocilizumab), at hospital discharge and at 3-months follow-up and sent to University Medical Centre Ljubljana, Slovenia for analysis. Statistics was performed by using SPSS 21.Results111 patients with COVID-19 pneumonia were recruited;7 patients died during hospitalisation (none were aPL-positive on admission and at the time of worsening), 3 due to pulmonary artery embolism. All patients were treated according to a predefined protocol which included antibiotics, corticosteroids, anticoagulation therapy and specific comorbidity drugs;patients with hypoxia were supported with oxygen. During hospitalisation, pulmonary artery thrombosis occurred in 5 patients, one was aPL-positive at all time points (was diagnosed with APS), others were negative. In addition, 9/101 patients had a history of thrombosis (5 arterial thrombosis (coronary and cerebral arteries), none of whom was aPL-positive on admission and at follow-up, and 4 venous thrombosis, one of which was aPL-positive at all time points and received an APS diagnosis). Among 9/101 patients with a history of thrombosis, 55.6% were transiently positive at the time of discharge, compared to patients without prior thrombosis, in whom 26.1% were transiently positive at the hospital release (p=0.074). Two patients had a history of pregnancy complications (both had miscarriage after 10th week of gestation), but did not have aPL positivity at any time point.ConclusionAlthough aPL was expected to be associated with vascular disease in the most severe forms of COVID-19, all patients that have died in our cohort were aPL negative. At hospital discharge, 56% of patients with a history of arterial or venous thrombosis had positive aPL that became negative at the 3-months follow-up (were transienlty positive), which should be considered when prescribing therapy after hospitalisation.References[1]Trahtemberg U, Rottapel R, Dos Santos CC, et al. Anticardiolipin and other antiphospholipid antibodies in critically ill COVID-19 positive and negative patients. Annals of the Rheumatic Diseases 2021;80:1236-1240.[2]Stelzer M, Henes J, Saur S. The Role of Antiphospholipid Antibodies in COVID-19. Curr Rheumatol Rep. 2021;23(9):72-4.[3]Xie Y, Wang X, Yang P, Zhang S. COVID-19 complicated by acute pulmonary embolism. Radiology: Cardiothoracic Imaging 2020: 2: e200067.[4]Miyakis S, Lockshin MD, Atsumi T, Branch DW, Brey RL, et al. J.Thromb.Haemost. 2006;4: 295-306.Acknowledgements:NIL.Disclosure of nterestsNone Declared.

Assessment of Jordanian physicians' knowledge about venous thromboembolism risk and management among COVID-19 patients

Objectives: The aim of this study was to assess Jordanian physicians' awareness about venous thromboembolism (VTE) risk among COVID-19 patients and its treatment protocol. Method(s): This was a cross-sectional-based survey that was conducted in Jordan in 2020. During the study period, a convenience sample of physicians working in various Jordanian hospitals were invited to participate in this study. Physicians' knowledge was evaluated and physicians gained one point for each correct answer. Then, a knowledge score out of 23 was calculated for each. Key Findings: In this study, 102 physicians were recruited. Results from this study showed that most of the physicians realize that all COVID-19 patients need VTE risk assessment (n = 69, 67.6%). Regarding VTE prophylaxis, the majority of physicians (n = 91, 89.2%) agreed that low molecular weight heparin (LMWH) is the best prophylactic option for mild-moderate COVID-19 patients with high VTE risk. Regarding severe/critically ill COVID-19 patients, 75.5% of physicians (n = 77) recognized that LMWH is the correct prophylactic option in this case, while 80.4% of them (n = 82) knew that mechanical prevention is the preferred prophylactic option for severe/critically ill COVID-19 patients with high bleeding risk. Moreover, 77.5% of physicians (n = 79) knew that LMWH is the treatment of choice for COVID-19 patients diagnosed with VTE. Finally, linear regression analysis showed that consultants had an overall higher knowledge score about VTE prevention and treatment in COVID-19 patients compared with residents (P = 0.009). Conclusion(s): All physicians knew about VTE risk factors for COVID-19 patients. However, consultants showed better awareness of VTE prophylaxis and treatment compared with residents. We recommend educational workshops be conducted to enhance physicians' knowledge and awareness about VTE thromboprophylaxis and management in COVID-19 patients.Copyright © 2022 The Author(s). Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved.

Caesarean section in critically unwell peri-partum patients with COVID-19: A tertiary centre's experience

Introduction: The COVID-19 pandemic has required clinical teams to function with an unprecedented amount of uncertainty, balancing complex risks and benefits in a highly fluid environment. This is especially the case when considering the delivery of a pregnant woman critically unwell with COVID-19. This is one maternal critical care team's reflections on establishing best practice and a shared mental model when undertaking a Caesarean section in critically unwell patients with COVID-19. Objective(s): We describe our experience of balancing the risks and streamlining the process of this high-risk intervention. Method(s): We used our standard clinical governance forums across four specialties (Obstetrics, Intensive care, Anaesthetics and Neonatology) to identify key challenges and learning points. We developed a working group to combine our learning and develop a shared mental model across the involved teams. Result(s): 1. The decision to deliver must be multidisciplinary involving Obstetrics, Intensive care, Anaesthetics, Neonatology and the patient according to their capacity to participate. The existing structure of twice daily ITU ward rounds could be leveraged as a 'pause' moment to consider the need for imminent delivery and review the risk-benefit balance of continued enhanced pharmacological thromboprophylaxis. 2. We identified a range of scenarios that our teams might be exposed to: 3. Perimortem Caesarean section 4. Critically unwell - unsafe to move to theatre 5. Critically unwell - safe to move to theatre 6. Recreating an obstetric theatre in the ICU Advantages Avoids moving a critically unstable patient, although our experience is increasing moving patients for ECMO. Some forms of maximal non-invasive therapy such as High Flow Nasal Oxygen may require interruption to move to theatre with resultant risk of harm or be difficult to continue in transport mode through a bulky ICU ventilator e.g. CPAP Disadvantages Significant logistics and coordination burden: multiple items of specialist equipment needing to be brought to the ICU. Human factors burden: performing a caesarean section in an unfamiliar environment is a significant increase in cognitive load for participating teams. Environmental factors: ICU side rooms may offer limited space vs the need to control the space if performed on an open unit. Delivering a Neonate into a COVID bubble. Conclusion(s): Developing a shared mental model across the key teams involved in delivering an emergency caesarean section in this cohort of critically unwell patients has enabled our group to own a common understanding of the key decisions and risks involved. We recommend a patient centred MDT decision making model, with a structure for regular reassessment by senior members of the teams involved. In most circumstances the human factors and logistical burden of recreating an operating theatre in the ICU outweighs the risk of transport to theatre. Pre-defined checklists and action cards mitigate the cognitive and logistical burden when multiple teams do perform an operative delivery in ICU. Action cards highlight key aspects of routine obstetric care to be replicated in the ICU environment.